This application relates to a refrigerant cycle having a common evaporator, but separate condensers, where one of the condensers is connected to an intermediate pressure compression stage, while the other condenser is connected to the high pressure compression stage.
Refrigerant cycles are utilized in applications to change the temperature and humidity or otherwise condition the environment. In a standard refrigerant system, a compressor delivers a compressed refrigerant to a heat exchanger, known as a condenser, which is typically located outside. From the condenser, the refrigerant passes through an expansion device, and then to an indoor heat exchanger known as an evaporator. At the evaporator, moisture may be removed from the air, and the temperature of air blown over the evaporator coil is lowered. From the evaporator, the refrigerant returns to the compressor. Of course, basic refrigerant cycles are utilized in combination with many configuration variations and optional features. However, the above provides a brief understanding of the fundamental concept.
Refrigerant cycles are known, wherein a so-called economizer circuit is incorporated. In an economizer circuit, a first refrigerant line is tapped from a main refrigerant line downstream of the condenser. The tapped refrigerant line is passed through an expansion device, and then the tapped refrigerant and the main refrigerant both flow through an economizer heat exchanger. The tapped refrigerant subcools the main refrigerant, such that when the main refrigerant reaches an evaporator, it will have a greater cooling potential. The tapped refrigerant, having subcooled the main refrigerant, is returned to the compressor at an intermediate compression point.
The present invention redirects the flow of refrigerant from an intermediate compression point in a compressor to selectively provide refrigerant to at least one of a plurality of condensers, where each of the condensers operate at different temperature levels. In this manner, the heat rejection characteristics of the refrigerant cycle can be controlled to provide a variety of options to a refrigerant cycle designer and to satisfy a wide spectrum of applications.